Grating structure



Nov. 23, 1948. R. WISELY GRATING STRUCTURE Filed June 21, 1945 Fig.4

INVENTOR. Robert Mire/y BY Patented Nov. 23, 1948 UNITED STATES PATENT OFFICE GRATING STRUCTURE Robert Wisely, Chicago, n1.

Application June 21, 1945, Serial No. 600,821

3 Claims. 1

The invention relates to grating of the type used in catwalks, stair treads, runways and is particularly well adapted for use in running boards for railway cars, where the gratings are made in sections and applied to the car in endto-end relation to provide running boards of varying lengths.

Metal running boards have replaced the old style wooden running boards on freight cars to a considerable extent during the past several years, due to their longer life and the fact that they provide safer footing for the trainmen who walk thereon; the tread surface of the metal running boards usually being serrated and the area of the tread surface being relatively open, to permit snow and ice pass therethrough.

To be acceptable to the railroads, metal running boards must meet certain specifications set up by the Interstate Commerce Commission and the Association of American Railroads, the principal requirements being resistance to deflection, under load, and the self-clearing properties. At the present time, the tread must be 50 per cent clear opening and the permissible deflection is 3/8 of an inch over an unsupported span of 48 inches, with a static load of 200 pounds applied at the center of the span.

Numerous gratings of the prior art do not have the required resistance to deflection to meet this specification while others do not have the required clear opening through the tread portion.

The type of metal running board most widely used on railway cars and the types which have been most satisfactory in meeting the specifications are shown, generally, in the Bates Patent No. 2,184,407 and the Nagin Patent No. 1,611,316. Both of these types are expensive to manufacture and require expensive and elaborate equipment and fixtures, such as multiple welding apparatus or heavy-duty presses of special design; this equipment being available in very few shops, as

it would be economically unsound for any shop to acquire this special equipment unless a sizeable amount of the available grating business were secured by such shops. This places gratings of the Bates and Nagin types at a disadvantage in price competition, limitsproduction to a few shops and limits the choice of manufacturers.

It is an important object of the present invention to provide an improved grating structure which may be made at low cost in practically any steel shop, without the use of other than ordinary steel shop equipment.

A further object is to provide a grating structure having maximum clear opening through the tread portion; all of the grating bars having their body portions disposed in a vertical plane.

Another object is to provide an improved grating structure wherein the longitudinal supporting bars have great strength to resist deflection, due to the fact that a small amount of metal has been struck therefrom, to accommodate the intersecting cross bars. Numerous grating structures are available which may be fabricated at low cost, but most of them involve the threading of the cross bars through the longitudinal supporting bars, requiring apertures through the longitudinal bars slightly larger than the crosssectional area of the cross bar, resulting in loss of strength and resistance to deflection of the supporting bar.

A supporting bar which has lost much of its resistance to deflection, due to relatively large apertures therethrough, might, to a certain degree, be compensated by using a heavier section of bar, but the added weight would be highly objectionable to railway car owners and would add-to the cost of a running board grating. The railroads endeavor to eliminate every ounce of unnecessary weight from the car structure, for which reason a heavy running board, of equal strength of a lighter running board, would be at a serious sales disadvantage.

Other advantages, objects and capabilities of my invention will appear as the description proceeds.

In the drawings:

Figure 1 is a plan view of one end portion of a section of my grating structure.

Fig. 2 is an enlarged, sectional view, taken along line 2-2 of Fig. 1.

Fig. 3 is an enlarged, sectional view, taken along line 3-3of Fig. 1.

Fig. 4 is a sectional view, taken along line 44 of Fig. 3.

Referring more particularly to the drawings, the illustrated embodiment of my invention includes spaced apart longitudinal supporting bars l0, spaced apart cross bars [2, marginal longitudinal bars [4 and marginal cross bars l6.

The longitudinal bar 10 may comprise a horizontally disposed flat metallic bar having its body portion in a vertical plane and may be provided along its upper edge with serrations I8 and spaced notches 20. An aperture 22 may be provided in the bar ID in underlying relation with the notch 20 and in the preferred embodiment of my invention I prefer to provide an aligned notch 20 and an aperture 22 coincident each intersection of a cross bar with a longitudinal bar, The aperture 22 may be considerably smaller than the cross sectional area of a cross bar l2 and may conform in size substantially with the cross-sectional area of a cooperating lug, hereinafter described. The end portions of the longitudinal bar it may be provided with shouldered extensions 2% of reduced size, for insertion through suitable apertures in the adjacent marginal cross bars l6 and may be rigidly secured to the bars It by bending the extensions 24 into flatwise engagement with the outer surface of the bars It.

The cross bar i2 may comprise a horizontally disposed fiat metallic bar having its body portion in a vertical plane and may be provided alon its upper edge with serrations l6 and along its lower edge with downwardly opening transverse slot 26. Each of the slots 26 is substantially twice as wide as the thickness of the longitudinal bars throughout its major length and is formed on one of its bounding edges with an integral lug 28 extending part of the way across the slot. This construction leaves an open space in each slot between the straight edge thereof and the end of the facing lug 28 at least equal to the thickness of a sup porting bar so that the supporting bars can be slipped into the slots to bring the apertures 22 therein into register with the lugs 28. Thereafter, when the cross bars are moved laterally of the supporting bars, the lugs 28 will enter the apertures 22, as shown in the drawing, to connect A the longitudinal and lateral bars. The ends of the cross bar l2 may be provided with shouldered extensions 38, similar to the extensions 24 of the longitudinal bars, for securing the cross barto the marginal longitudinal bars M,

The marginal longitudinal bar i l may comprise a horizontally disposed flat metallic bar having its body portion disposed in a vertical plane and may be provided along its upper edge with serration l8 and a series of closed-perimeter apertures 32 below said edge coincident with the end portions of the cross bars 52, said apertures being adapted to receive the extensions 35 of the cross bars, said extensions 39 being bent over against the outer surface of the bar M-to rigidly secure the cross bars to the marginal longitudinal bars.

The marginal cross bar l6 may comprise a horizontally disposed fiat bar having its body portion disposed in a vertical plane and may be provided along its upper edge with serrations i8 and an underlying series of apertures coincident with the extensions 24 of the longitudinal bars ill whereby the ends or the longitudinal bars may be rigidly secured to the marginal cross bar it by bending over the extensions 24. The opposed ends of the cross bar l8 may be bent at right angles to the bar and secured to the ends of the marginal bars I .4 in any suitable manner, as by welding or rivetmg.

It will be understood that the marginal bars 14 and I6 may comprise shapes other than fiat bars and they may be made of heavier sections than the bars ill and I2 if desired, inasmuch as they are intended to act as a frame for the intermediate grating.

I prefer to secure one end of each cross bar I2 to the adjacent marginal bar Hi under a slight tension, the end under tension being the end facing the associated lugs 28 of the cross bar, whereby after securing the said one end to the adjacent marginal bar [4, the said associated lugs 28 will be normally urged in a direction adapted to hold them in tight engagement with the apertures 22 of the intersecting bars lll.

I prefer to arrange the cross bars of the grating structure so the lugs of one cross bar will face in the opposite direction to the lugs of the cross bar next adjacent, throughout the length of the grating. The beforementioned tension in the aligned end portions of the cross bars will occur at every second cross bar throughout the length of each marginal longitudinal bar, in the preferred embodiment of my invention, It will be understood that .the marginal longitudinal bars may be bowed inwardly, slightly, at point of securement of the tensioned end of each cross bar to said marginal longitudinal bar.

It will be understood that the cross bars may be arranged otherwise than as indicated for my preferred arrangement thereof, without departing from the scope of my invention.

The gratin may be assembled by securing the longitudinal supporting bars I!) in parallel spaced side-by-side relation and securing them in fixed relation by inserting the opposed extensions 24 of each bar It through the apertures in the opposed .marginal'cross bars l6 and bending the extensions 2 i into holding relation with the bars I6, as shown in Fig. l of the drawings. The cross bars l2 may then beplaced transversely of and in supported relation with the supporting bars It], with the lugs 28 of each cross bar l2 in registe ing relation with the aligned apertures 22 of the bars 9. The lugs 28 of alternate cross bars l2 preferably extend in opposite directions through out the length of a grating section; this alternate arrangement of the lugs being adapted to maintain the lugs of :the assembled grating in interlocked engagement with the supporting bars l0. After the cross bars 12 are disposed in supported relation with the upper edges of the aligned bars iii, alternatecross bars l2 may be moved axially in opposite directions into interlocked relation with the bars). The opposed bars It may then be affixed to the adjacent ends of the cross bars I? and secured in place by bending the extensions 30 over, as-shown in Fig. 1. The opposed ends of the marginal bars 15 may be bent over the adjacent ends of the marginal bars M and secured in place by rivets, Welding or other suitable securing means. It will be understood that the spaced apart supporting bars H! may be secured in fixed relation with each other by means of the marginal bar It and that the cross bars 12 may be applied to the bars 10 without disturbing this fixed relationship of the bars It). It will also be understood that a damaged cross bar i2 can be readily removed and replaced without disturbing the rest of the bars I 0 or the bars i2; this being an important advantage where the grating is used as a railway car-runn'ing-board as the latter is subject to rough usage and damage.

I claim:

1. A grating structure comprising spaced longitudinal bars and spaced cross bars, said longitudinal bars having spaced notches in their upper edges and spaced a-l'zvertures below said notches, said cross bars having spaced lateral elongate slots each substantially twice as wide as the thickness of a longitudinal bar through their major lengths, a single longitudinal'bounding edge of each of the said slots in each cross bar being provided with a lug extending part way across the slot, to leave an open space in each slot between the straight edge thereof and the end of the facing lug, at least as great as the thickness 'of-a longitudinal bar, the assembled bars being interlocked with the upper extremities of said slots in nested relation with said notches and with said-lugs in nested relation with said apertures, all the lugs of a plurality of the assembled cross bars facing in one direction and all the lugs of the remaining cross bars facing in the opposite direction.

2. The structure of claim 1 wherein the lugs of'the assembled cross bars face in alternate directions.

3. The structure of claim 1 wherein the fitted interlocked bars of the grating are secured against relative movement by securing the ends of each of the bars to a marginal bar disposed transversely with respect to the bars so secured, the end portions of the cross bars facing the lugs thereof being secured to a marginal bar under tension to normally urge the cross bars in a direction to hold the lug-carrying side edges of the slots in abutting engagement with the side walls of the intersecting longitudinal bars and hold the lugs in interlocked relation with the registering apertures of the last named bars.

ROBERT WISELY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,428,230 Hess Sept. 5, 1922 1,573,154 Gelder Feb. 16, 1926 1,669,236 Fick May 8, 1928 2,037,889 Doud Apr. 21, 1936 2,396,735 Leigh Mar. 19, 1946 FOREIGN PATENTS Number Country Date 138,418 Great Britain Feb. 12, 1920 

